The disclosure relates generally to the control of a compression system with independently actuated inlet guide and/or stator vanes, and, more particularly, to a method and apparatus for control of a gas turbine with such vanes.
Modern gas turbine compression systems must operate over a wide set of conditions, including varying flows, speeds, pressure ratios, and ambient conditions, while addressing multiple, often conflicting requirements such as efficiency and operability. The control of gas turbine compression systems is typically limited to one degree of freedom, which limits the extent to which the control system can tradeoff competing objectives such as efficiency and operability. A system with more degrees of freedom, such as a two degree of freedom compression system, would provide the opportunity for improved control of competing requirements such as efficiency and operability as compared with the traditional one degree of freedom compression system. For example, a two degree of freedom gas turbine system could have enhanced turndown capability with superior operating efficiency as compared with typical systems, an improvement in the efficacy of on-line compressor water-wash systems, and/or improved compressor stability over a wide range of power plant operations, including startup and shutdown transients and hot-day lapse rate.